With increasing worldwide CO2 emissions, interest has risen in injecting CO2 into coals to mitigate their possible role in global warming. Concepts from natural gas storage are readily adapted to CO2 sequestration in coals. The classic p/Z plot for describing stored gas inventories is modified for CO2 sequestration using the p/Z* concept developed for understanding conventional coal gas recovery. Coal often exhibits stress dependent permeability and this relationship is used to identify the optimal depth for CO2 injection. CO2 fillup of a coal seam is described by coupling a gas injectivity equation with a mass balance equation. Example calculations are presented for two selected basins.

You can access this article if you purchase or spend a download.